LIMAX. 135 



worms. Its slime is abundant and viscous, feeling like 

 a lump of sticky fat. MUller states that when it is 

 touched it draws in its horns and remains all day as if it 

 were dead, but in the evening it recovers itself. It is 

 extremely prolific, producing several families, averaging 

 fifty each, in the course of the breeding-season, viz. from 

 April to November. According to Leuch, a German 

 naturalist, a pair of these slugs have been known to lay 

 776 eggs. These eggs have retained their vitality and 

 the young have been developed from them after having 

 been dried eight times successively in a furnace. It has 

 the same faculty as L. arborum of letting itself down 

 from one branch of a tree to another or to the ground, 

 by means of a slimy thread. Mr. Norman informs me 

 that in the earlier part of the year this slug is usually 

 creamy-white or light-drab ; that as the summer passes 

 away it assumes a darker hue, and brown flakes are 

 more or less thickly scattered over the surface; and 

 that during the autumn it is frequently of a rich brown 

 colour. A monstrosity of L. agrestis was found by Mr. 

 Gibbs, having the upper tentacles united into one. 



Lister first distinguished the field-slug from other 

 kinds by its smaller size and the nature of its slime; 

 and he also described its shell by appropriate characters. 

 This shell is the Limacella obliqua of Brard. 



5. L. ARBORUM *, Bouchard-Chantereaux. 



L. arborum, Bouch.-Chant. Moll. Pas-de-Cal. p. 28 ; F. & H. iv. p. 17, 

 pi. E. E. E. f. 2 (as L. arboreus). 



Body rather slender, gelatinous, sea-green or bluish-grey 

 with irregular yellowish-white spots, indistinctly streaked with 

 a darker colour down the sides, leaving a Hghter stripe in the 

 middle from the shield to the tail, finely wrinkled : shield 



* Inhabiting trees. 



